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11.
High parallelization efficiency in barotropic-mode computation of ocean models based on multi-grid boundary ghost area 总被引:1,自引:0,他引:1
In general, barotropic-mode computation requires the largest communication time in ocean models because of its iterative nature, when parallel computation is performed based on regional partitioning. In this study, reduction in the overhead time included in the communication in the parallel computation of the barotropic mode is considered to achieve a high parallelization efficiency of ocean models. We verify that the reduction in the communication frequency based on the multi-grid boundary ghost area reduces the total communication time. We find that this is because the sum of several kinds of overhead time for communication occupies a fairly large part of the total communication time. We discuss the trade-off between the decrease in communication time and the increase in computation time due to increased boundary area in such cases, leading to a determination of a suitable width of the multi-grid boundary that minimizes the total required time. We also discuss the efficiencies of the one- and two-dimensional partitioning of the model domain, when a multi-grid boundary is used. In general, two-dimensional partitioning is more efficient than one-dimensional for large partitioning numbers. 相似文献
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钢筋混凝土桩网复合地基是一种新的地基处理技术。本文对适用于钢筋混凝土桩网复合地基沉降计算的方法进行探讨。 相似文献
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The advent of the Virtual Observatory has begun an evolution in the space physics data environment. A number of nascent and
discipline specific Virtual Observatories have started to emerge with an emphasis on data search and retrieval. As this new
data environment takes shape an emphasis will be placed on interdisciplinary communication in attempts to address large scale
and global problems. To this end we formulate the development of a query language to facilitate Virtual Observatory to Virtual
Observatory communication. Furthermore, we outline the goals of such a language, how it would work and how existing community
efforts can be leveraged to speed the development of this query language.
相似文献
T.W. NarockEmail: |
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Land use change has been recognized throughout the Earth as one of the most important factors influencing the occurrence of rainfall-driven geomorphological processes. However, relating the occurrence of historical soil erosion rates is difficult because of the lack of long-term research projects in river basins. Also, complex models are not adequate to reconstruct erosion rate changes because they require significant input data not always available on long timescales. Given the problems with assessing sediment yield using complex erosion models, the objective of this study is to explore a parsimonious scale-adapted erosion model (ADT) from the original Thornes and Douglas algorithms, which aims at reconstruction of annual net erosion (ANE) upon multisecular timescales. As a test site, the Calore River basin (3015 km2 in southern Italy) provides a peculiar and unique opportunity for modelling erosion responses to climate and land cover changes, where input-data generation and interpretation results were also supported by documented hydrogeomorphological events that occurred before and after land deforestation. In this way, ANEADT-values were reconstructed for the period 1675–2004 by using precipitation indexes, complemented by recent instrumental records, and by using land cover statistics from documented agrarian sources. Pulses of natural sedimentation in the predeforestation period have been related to Vesuvius volcanic activity and changes in rainstorm frequency. After deforestation, the basin system became unstable with sudden fluctuations in the hydrogeomorphological regime contributing significantly to increased erosion and, in turn, sediment transport sequences via river drainage towards the Tyrrhenian coast. 相似文献
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本文简要地介绍了办公自动化的发展过程,分析了其常用的功能、特点,以及内容分类,论述了目前办公自动化系统的技术支撑和实现,并指出政府办公自动化系统在开发和应用中存在的问题和解决思路。对系统的推广使用具有一定的参考意义。 相似文献
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介绍一种IP传输方案。该方案通过地震数据IP传输及存储单元(ITU)、IP流多串口服务器完成,能实现单个台站与多个台网中心的Internet传输、单个台站与多个台网中心的专线传输、地震台网中心之间的Internet连接、远程数据下载及参数设置等多种传输方式,该传输方案具备实时性、可压缩性、多路服务、安全性、数据在线保存、传输费用低、操作简单等特点。 相似文献
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以内蒙古为例,探讨了内陆待开发地区的产业发展模式,内陆待开发地区经济发展的主要制约因素是缺乏资金,缺乏技术,缺乏人才,因此,其经济发展必须有选择,有重点地优先发展部分行业。一般说来,待开发的内陆地区其经济发展必须以资源优势为依托,以市场为导向,开发优质名牌产品,发展优势产业,建设主导产业,带动地区经济的起飞。 相似文献